Novel imaging process



y 21, 1954 n. A. NEWMAN 3,1 4

novsr. IMAGING PROCESS Filed April 12, 1961 INVENTOR. fioqqlas A. A ewma/z/ HTTOE EYS United States Patent O 3,141,404 NOVEL IMAGING PROCESS Douglas A. Newman, Glen Cove, N.Y., assignor to Columbia Ribbon and Carbon Manufacturing Co., Inc, Glen Cove, N.Y., a corporation of New York Filed Apr. 12, 1961, Ser. No. 102,598 5 Claims. (Cl. 101149.5)

This invention relates to the novel method for placing magnetizable images on the surface of a copy sheet directly from a master sheet having thereon images comprising an infrared radiation-absorbing heat meltable composition.

The field of automatic sensing of magnetic images has taken on an ever-increasing importance due tothe widespread use and improvement of automatic data process ing equipment by the government, large business firms, banks and the like.

In the sensing of magnetic images, a copy sheet or record card bearing such images is introduced into processing equipment containing a suitable sensing device such as a reading head assembly which produces electrical signals when magnetized areas are passed across the reading head. These electrical signals are analyzed by the processing equipment which automatically determines the identity of the sensed character, and then records, sorts, computes or duplicates the same depending upon the nature of the equipment used.

As can be readily understood the accuracy of the sensing equipment depends almost entirely upon the sharpness and clarity of the magnetic images being sensed. Certain images are very similar to others, and when these images are not sharply and clearly defined, there is a possibility of the images being misread by the sensing device. Likewise a ragged edge or a void on the image can distort the electrical signal generated by the image.

Up to the present, copy sheets and cards for use with automatic sensing devices have had to be printed or imaged manually using suitable magnetic transfer sheets or ribbons, and when sensible duplicates were desired they had to be printed or manually imaged.

It is an object of this invention to prepare master sheets, carrying magnetizable images, which may be used to image several duplicate copy sheets or record cards with corresponding magnetizable images.

It is another object of this invention to produce pressure-sensitive transfer sheets containing magnetic pigment, which sheets may be used to apply heat-duplicating magnetic images on a master sheet or card.

It is a further object of this invention to produce master sheets or cards having magnetic images thereon which may be transferred in part to a series of copy sheets under the effects of selective infrared radiation heating to produce several duplicate magnetically sensible copies of the original master sheet or card.

It is an advantage of the present invention that several duplicate magnetically sensible copies may be made while only typing upon a transfer sheet once to produce the master.

It is another advantage of this invention that magnetically sensible master sheets and cards may be removed from the files and duplicated simply and Without the use of special duplicating copy papers.

These and other objects and advantages are accomplished as more fully set out hereinafter.

In the drawing:

FIGURE 1 is a perspective view of an imaged master sheet or card shown together with magnetic transfer sheet 20, the master having images 11 thereon pressuretransferred from the transfer layer 21 of the transfer sheet.

FIG. 2 is a diagrammatic cross section, to an enlarged ice scale, of the imaged master 10 superposed with a copy sheet 30, separated for purposes of illustration, and under the effects of infrared radiation 50.

FIG. 3 illustrates the sheet of FIG. 2, after irradiation, demonstrating the magnetically sensible images 30a transferred from sheet 10 to copy sheet 30 by means of heat.

The transfer sheets of the present invention are prepared by coating a suitable flexible plastic or paper foundation sheet with a suitable pressure-transferable magnetic composition having the property of fusing and becoming tacky and adhesive under the effects of the heat generated by absorbed infrared radiation.

The composition of the transfer layer 21 forms a critical part of the present invention in that such composition becomes transferred to the copy sheet or record card surface in the form of images 30a which are magnetically sensible and thus must be of such precise sharpness and clarity as to function properly in magnetic processing equipment. The transfer composition must be both heatand pressure-transferable. It must have the property of absorbing infrared radiation and to a degree suflicient to reduce the composition to a fused, tacky and adhesive condition. Finally, the transfer composition must contain magnetically sensible pigment.

Additionally it has been found preferable that the transfer composition be so constituted as to have no sharp melting temperature so that the fusing and melting of the composition in the form of images 11 take place over a temperature range of several degrees. In this manner, the images first soften and become tacky and adhesive and thus adhere sharply to the copy sheet or record card surface and the over-all melting of the images occurs slowly and gently. If a composition having a sharp melting temperature is employed, then the images 11 liquefy suddenly and abruptly and tend to spread on the copy sheet surface causing the formation of wide blurred images which cannot be accurately sensed by the processing equipment. Excellent results have been obtained when the transfer composition contains a mixture of different binder materials, either waxes or thermoplastic resins, and preferably mixtures thereof, having different melting temperatures. The following examples are illustrative of suitable transfer compositions, and are set forth by way of illustration rather than limitation.

Example 1 Ingredients: Parts by weight Carnauba wax 35 Indopol I-I-300 (polymerized butene isomers) 15 Black iron oxide 40 Mineral oil 10 Example 2 Ingredients:

Raw montan wax 40 Carnauba wax 5 Vistanex (polyisobutylene) 10 Black iron oxide 30 Carbon black 10 Rapeseed oil 5 Example 3 Ingredients:

Carnauba wax 30 Microcrystalline wax 10 Tornesit (chlorinated rubber) 10 Black iron oxide 35 Lanolin 5 Mineral oil 10 It is important that the transfer compositions used with the present mvention have a melting temperature which 1s withln the temperature range of from about C.

to about 250 C. and contain an infrared radiation-absorbing pigment in an amount sufficient to generate the necessary melting temperature. It is preferred for this purpose to use black iron oxide which functions both as the magnetic pigment and the infrared radiation absorber. However, other magnetic pigments such as red iron oxide, iron filings and iron powder may be employed, together with other radiation-absorbing pigments such as carbon black, nigrosine and the like. It is preferred that the magnetic pigment and the radiation-absorbing pigment be present in an amount equal to from about 30 percent to about 60 percent based upon the total weight of the transfer composition.

The transfer composition preferably has a relatively high melting point in excess of about 150 C. and thus comprises higher melting point waxes such as carnauba and raw montan wax as the major part by weight of the binder mixture. Also it is preferred that the binder mixture contain a thermoplastic resin material such as ethyl cellulose, polyvinyl butyrate, Arochlor (chlorinated biphenyl) and others, including those shown in the foregoing examples.

The master sheet or card 110 to be imaged with any of the above compositions is preferably translucent or transparent and may be paper or a plastic film such as Mylar (polyethylene terephthalate), polyvinyl fluoride, polyethylene or the like, preferably frosted, undercoated or otherwise treated to render the surface more receptive to the transfer composition. The master sheet is preferably imaged with mirror-reverse images by placing the master against the transfer layer of transfer sheet 20 and typing against the back of the master to produce reverse images as illustrated by FIG. 1 of the drawing.

The master having pressure-inscribed images 11 thereon is next superposed with any suitable copy sheet or record card 30 so that the images are in contact with the copy surface. The sheets are then subjected to a light source 50 rich in infrared radiation which is directed against the back of the master, as shown in FIG. 2, for a period of time sufiicient to fuse and melt the images and allow them to adhere to the copy surface. Upon removal of the sheets from the radiation source and separation thereof, portions of the images 11 have been picked off by the copy surface in the form of direct-reading magnetically sensible images 30a, as shown by FIG. 3, leaving remnant portions 11a on the master sheet available for the imaging of several additional copy sheets or record cards in the same manner. The master sheet retains its original property of also being magnetically sensible and may be automatically processedand filed until additional copies are desired. i

It has been found that the use of infrared radiation forms a critical part of the present invention in that it allows for selective heating of the images on the master sheet or card without materially heating the master sheet foundation or the copy sheet or card. The heated images transfer sharply and cleanly to the relatively cool copy surface, and this is critical in the magnetic sensing field where the accuracy of the sensing process depends ultimately upon the quality of the magnetic images 30a on the copy sheet or record card. It has been found that when heat is used to cause transfer, rather than infrared radiation, then the master sheet and copy sheet or record card are also heated over-all and the images 11 tend to lose their sharpness by melting and spreading on the warm or hot master sheet, and by being even further spread by the warm or hot surface of the copy sheet, thereby resulting in dull or fuzzy images on the copy sheet or record card which cannot be accurately sensed by magnetic data processing equipment.

No particular criticality exists with respect to the source of infrared radiation employed and infrared ray lamps, carbon arcs and photoflash lamps provide excellent results. It is generally preferred to employ any convenient fiat bed apparatus or belt machine such as the Thermo- Fax machine. The duration of exposure of the sheets is continued for only that period of time sufficient to reduce the images 11 to a tacky melted condition, generally anywhere from instantaneous to about five or ten seconds, depending upon the proximity and strength of the radiation source.

Variations and modifications may be made within the scope of the claims and portions of the improvements may be used without others.

I claim:

1. The method of placing on a copy sheet sharp clear magnetically-sensible images which are devoid of ragged edges, said method comprising the steps of superposing a copy sheet in surface contact with the images on a master sheet, said images being infrared radiation-absorbing and containing magnetically-sensible pigment dispersed in a binder material having a broad melting range so that melting of the images takes place over a temperature range of several degrees, directing a sufficient quantity of radiation rich in infrared against the superposed sheets so that it is selectively absorbed by the images on the master sheet and gradually heats them to their melting range without materially heating the master sheet and the copy sheet, whereby the images soften and become tacky without abrupt liquefication and adhere to the surface of the copy sheet in sharp clear image form, and separating the copy sheet from the master sheet to provide on the copy sheet said sharp clear magnetically-sensible images which are devoid of ragged edges which would cause a distorted signal to be generated by the images in the magnetic sensing process.

' 2. The method according to claim 1 in which the binder material for the magnetically sensible pigment is a wax composition.

3. The method according to claim 1 in which the binder material for the magnetically-sensible pigment is a resinous composition.

l 4. The method according to claim 1 in which the binder material for the magnetically-sensible pigment is a mixture of wax and resin.

5. The method according to claim 1 in which the magnetically-sensible pigment comprises black iron oxide.

References Cited in the file of this patent UNITED STATES PATENTS 2,501,495 Carroll et al Mar. 21, 1950 2,744,031 Mumma May 1, 1956 2,808,777 Roshkind Oct. 8, 1957 2,954,311 Vander Weel Sept. 27, 1960 

1. THE METHOD OF PLACING ON A COPY SHEET SHARP CLEAR MAGNETICALLY-SENSIBLE IMAGES WHICH ARE DEVOID OF RAGGED EDGES, SAID METHOD COMPRISING THE STEPS OF SUPERPOSING A COPY SHEET IN SURFACE CONTACT WITH THE IMAGES ON A MASTER SHEET, SAID IMAGES BEING INFRARED RADIATION-ABSORBING AND CONTAINING MAGNETICALLY-SENSIBLE PIGMENT DISPERSED IN A BINDER MATERIAL HAVING A BROAD MELTING RANGE SO THAT MELTING OF THE IMAGES TAKES PLACE OVER A TEMPERATURE RANGE OF SEVERAL DEGREES, DIRECTING A SUFFICIENT QUANTITY OF RADIATION RICH IN INFRARED AGAINST THE SUPERPOSED SHEETS SO THAT IT IS SELECTIVELY ABSORBED BY THE IMAGES ON THE MASTER SHEET AND GRADUALLY HEATS THEM TO THEIR MELTING RANGE WITHOUT MATERIALLY HEATING THE MASTER SHEET AND THE COPY SHEET, WHEREBY THE IMAGES SOFTEN AND BECOME TACKY WITHOUT ABRUPT LIQUEFICATION AND ADHERE TO THE SURFACE OF THE COPY SHEET IN SHARP CLEAR IMAGE FORM, AND SEPARATING THE COPY SHEET FROM THE MASTER SHEET TO PROVIDE ON THE COPY SHEET SAID SHARP CLEAR MAGNETICALLY-SENSIBLE IMAGES WHICH ARE DEVOID OF RAGGED EDGES WHICH WOULD CAUSE A DISTORTED SIGNAL TO BE GENERATED BY THE IMAGES IN THE MAGNETIC SENSING PROCESS. 